Osimertinib Plus Durvalumab in Patients With EGFR-Mutated, Advanced NSCLC: A Phase 1b, Open-Label, Multicenter Trial.

INTRODUCTION: EGFR tyrosine kinase inhibitors (TKIs) are recommended for EGFR-mutated NSCLC treatment. EGFR activation up-regulates programmed death-ligand 1 expression and other immunosuppressive factors in NSCLC, causing immune microenvironment remodeling. Osimertinib (an EGFR TKI) plus durvalumab (programmed death-ligand 1 blockade) was evaluated in the TATTON study (NCT02143466). METHODS: This open-label, phase 1b study enrolled patients with advanced EGFR-mutated NSCLC. In part A, patients who had progressed on a previous EGFR TKI received osimertinib (80 mg once daily) plus durvalumab 3 or 10 mg/kg every 2 weeks. In part B, patients received first-line osimertinib plus durvalumab 10 mg/kg every 2 weeks. However, part B enrollment was terminated early owing to an increased incidence of interstitial lung disease (ILD)-related adverse events (AEs). Safety (primary objective) and preliminary anti-tumor activity determined by objective response rate (ORR), best overall response, duration of response (DOR), and progression-free survival were evaluated. RESULTS: Before enrollment termination, 23 and 11 patients received treatment across parts A and B, respectively. The most common AEs across parts A and B were as follows: diarrhea (50%), nausea (41%), and decreased appetite (35%). A total of 12 patients (35%) reported ILD-related AEs (lung disorder, ILD or pneumonitis). In part A, ORR was 43% (95% confidence interval [CI]: 23-66); median DOR was 20.4 months. In part B, ORR was 82% (95% CI: 48-98), median DOR was 7.1 months, and median progression-free survival was 9.0 months (95% CI: 3.5-12.3). CONCLUSIONS: This study highlighted a potential risk of ILD-related AEs when combining osimertinib with durvalumab. Further research looking to combine EGFR TKIs with immune checkpoint inhibitors should be approached with caution.

Comparison of the Pharmacokinetics of the Phase II and Phase III Capsule Formulations of Selumetinib and the Effects of Food on Exposure: Results From Two Randomized Crossover Trials in Healthy Male Subjects.

PURPOSE: Selumetinib (AZD6244, ARRY-142886), an oral, potent, and highly selective mitogen-activated protein kinase 1/2 inhibitor with a short half-life, has shown activity across various tumor types. Before initiation of Phase III trials, the site, scale, and color (hypromellose shell from white [Phase II] to blue [Phase III]) of the selumetinib 25mg capsule manufacture was changed. We present 2 crossover trials evaluating Phase III capsules in healthy subjects. METHODS: The relative bioavailability trial was a Phase I, open-label, randomized, 3-treatment, 4-period, 6-sequence crossover trial in healthy male subjects (aged 18-55 years). Subjects received selumetinib 75mg (3 × 25 mg) Phase II or Phase III capsules, or a 35mg oral solution, during 4 dosing periods in 1 of 6 randomized treatment sequences. The food effect trial was a Phase I, open-label, randomized, 2-period crossover trial in healthy male subjects (aged 18-45 years). Subjects were randomized to 1 of 2 sequences to receive selumetinib 75mg (3 × 25 mg) Phase III capsules. In sequence 1, subjects received selumetinib after 10 hours of fasting. Following a washout period, selumetinib was administered after a high-fat meal. In sequence 2, subjects received selumetinib in the fed state, before the fasted state. Pharmacokinetic parameters were determined from serial blood sampling. FINDINGS: Twenty-seven subjects were randomized to the relative bioavailability trial; 26 completed all dosing periods. Mean selumetinib AUC was unchanged (geometric least squares mean ratio [GLSMR], 90.01% [90% CI, 81.74-99.11]). Cmax was 18% lower with the Phase III capsules (GLSMR, 81.97% [90% CI, 69.01-97.36]). A post hoc exploratory statistical analysis excluding outlying observations with later Tmax showed that Phase II and III capsules produced similar exposure in terms of Cmax and AUC. High intrasubject variability for Cmax attributed to the pharmacokinetic sampling schedule was judged to have impacted on the estimated GLSMR. In the food effect trial, 34 subjects completed both study periods. A high-fat meal reduced selumetinib Cmax compared with the fasted state (GLSMR, 49.76% [90% CI, 43.82-56.51]); AUC was minimally changed (GLSMR, 84.08% [90% CI, 80.72-87.59]). Median Tmax was prolonged by 1.49 hours. No deaths or serious adverse events were reported. IMPLICATIONS: Selumetinib 75mg (3 × 25 mg) Phase III capsules are being used in ongoing pivotal Phase III trials and should be administered in the fasted state. Based on findings from the relative bioavailability trial, pharmacokinetic sampling frequency was increased for healthy subject trials, including the food effect trial. ClinicalTrials.gov identifiers: NCT01635023 (relative bioavailability) and NCT01974349 (food effect).

SELECT-3: a phase I study of selumetinib in combination with platinum-doublet chemotherapy for advanced NSCLC in the first-line setting.

BACKGROUND: We investigated selumetinib (AZD6244, ARRY-142886), an oral, potent, and highly selective, allosteric MEK1/2 inhibitor, plus platinum-doublet chemotherapy for patients with advanced/metastatic non-small cell lung cancer. METHODS: In this Phase I, open-label study (NCT01809210), treatment-naïve patients received selumetinib (50, 75, 100 mg BID PO) plus standard doses of gemcitabine or pemetrexed plus cisplatin or carboplatin. Primary objectives were safety, tolerability, and determination of recommended Phase II doses. RESULTS: Fifty-five patients received treatment: selumetinib 50 or 75 mg plus gemcitabine/cisplatin (n=10); selumetinib 50 mg plus gemcitabine/carboplatin (n=9); selumetinib 50, 75 or 100 mg plus pemetrexed/carboplatin (n=21); selumetinib 75 mg plus pemetrexed/cisplatin (n=15). Most frequent adverse events (AEs) were fatigue, nausea, diarrhoea and vomiting. Grade ⩾3 selumetinib-related AEs were reported in 30 (55%) patients. Dose-limiting toxicities (all n=1) were Grade 4 anaemia (selumetinib 75 mg plus gemcitabine/cisplatin), Grade 4 thrombocytopenia/epistaxis and Grade 4 thrombocytopenia (selumetinib 50 mg plus gemcitabine/carboplatin), Grade 4 febrile neutropenia (selumetinib 100 mg plus pemetrexed/carboplatin), and Grade 3 lethargy (selumetinib 75 mg plus pemetrexed/cisplatin). Partial responses were confirmed in 11 (20%) and unconfirmed in 9 (16%) patients. CONCLUSIONS: Standard doses of pemetrexed/carboplatin or pemetrexed/cisplatin were tolerated with selumetinib 75 mg BID. The selumetinib plus gemcitabine-containing regimens were not tolerated.

Pharmacokinetics and pharmacogenetics of the MEK1/2 inhibitor, selumetinib, in Asian and Western healthy subjects: a pooled analysis.

PURPOSE: Emerging data on selumetinib, a MEK1/2 inhibitor in clinical development, suggest a possible difference in pharmacokinetics (PK) between Japanese and Western patients. This pooled analysis sought to assess the effect of ethnicity on selumetinib exposure in healthy Western and Asian subjects, and to identify any association between genetic variants in the UGT1A1, CYP2C19 and ABCG2 genes and observed differences in selumetinib PK. METHODS: A pooled analysis of data from ten Phase I studies, one in Asian subjects (encompassing Japanese, non-Japanese Asian and Indian Asian subjects) and nine in Western subjects, was conducted. Key findings were derived from the collective exposure data across doses of 25, 35, 50 and 75 mg selumetinib; primary variables were dose-normalized AUC and Cmax. RESULTS: PK data from 308 subjects (10 studies) were available for the pooled analysis; genetic data from 87 subjects (3 studies) were available for the pharmacogenetic analysis. Dose-normalized AUC and Cmax were 35% (95% CI: 25-47%) and 39% (95% CI: 24-56%) higher in the pooled Asian group, respectively, compared with Western subjects. PK exposure parameters were similar between the Japanese, non-Japanese Asian and Indian groups. There was no evidence that the polymorphisms assessed in the genes UGT1A1, CYP2C19 and ABCG2 account for observed PK differences. CONCLUSIONS: Selumetinib exposure was higher in healthy Asian subjects compared with Western subjects, and these data provide valuable insight for clinicians to consider when treating patients of Asian ethnicity with selumetinib.

Effects of cytochrome P450 (CYP3A4 and CYP2C19) inhibition and induction on the exposure of selumetinib, a MEK1/2 inhibitor, in healthy subjects: results from two clinical trials.

PURPOSE: Two phase I, open-label trials in healthy subjects assessed whether co-administration with CYP3A4/CYP2C19 inhibitors, itraconazole/fluconazole (study A), or CYP3A4 inducer, rifampicin (study B), affects the exposure, safety/tolerability and pharmacokinetics of selumetinib and its metabolite N-desmethyl selumetinib. METHODS: In study A (n = 26), subjects received a single dose of selumetinib 25 mg and, after 4 days of washout, were randomized to treatment 1 (itraconazole 200 mg twice daily on days 1-11) or treatment 2 (fluconazole 400 mg on day 1 then 200 mg/day on days 2-11) plus co-administration of single-dose selumetinib 25 mg on day 8 (selumetinib staggered 4 h after itraconazole/fluconazole dose); Twenty-one days after discharge/washout, subjects received the alternate treatment. In study B (n = 22), subjects received a single dose of selumetinib 75 mg (day 1) then rifampicin 600 mg/day (days 4-14) plus a single dose of selumetinib 75 mg on day 12. Pharmacokinetic analysis and safety assessments were performed. RESULTS: Selumetinib co-administered with itraconazole, fluconazole (selumetinib staggered 4 h after itraconazole/fluconazole dose), or rifampicin was well tolerated. Selumetinib exposure was higher when co-administered with itraconazole or fluconazole (area under the plasma concentration-time curve (AUC) increased by 49 and 53%, respectively; maximum plasma concentration (C max) increased by 19 and 26%, respectively) but lower when co-dosed with rifampicin (AUC and C max decreased by 51 and 26%, respectively) versus selumetinib dosed alone. Co-administration with itraconazole or rifampicin decreased N-desmethyl selumetinib AUC(0-t) (11 and 55%, respectively), and C max (25 and 18%, respectively), with fluconazole, AUC(0-t) increased by 40%, but there was no effect on C max. CONCLUSIONS: Co-administration of CYP3A4/CYP2C19 inhibitors will likely increase exposure to selumetinib, while CYP3A4 inducers will likely reduce its exposure.

Pharmacokinetics of a Single Oral Dose of the MEK1/2 Inhibitor Selumetinib in Subjects With End-Stage Renal Disease or Varying Degrees of Hepatic Impairment Compared With Healthy Subjects.

Two phase I open-label studies were conducted to investigate the pharmacokinetics (PK), safety, and tolerability of single oral doses of selumetinib in subjects with end-stage renal disease (ESRD) undergoing hemodialysis and subjects with varying degrees of hepatic impairment; both studies included a matched control group comprised of healthy individuals. In the renal impairment study, subjects received single doses of selumetinib 50 mg; those with ESRD received selumetinib before and after dialysis (with a between-treatment washout period of ≥7 days). In the hepatic impairment study, subjects received varying single doses of selumetinib (20-50 mg) depending on liver dysfunction (mild, moderate, or severe as per Child-Pugh classification). PK, safety, and tolerability data were collected from both studies. Overall, 24 subjects were included in the renal impairment study (ESRD, N = 12; healthy subjects, N = 12). Selumetinib exposure (AUC and Cmax ) was not increased in the ESRD group vs healthy subjects. Selumetinib exposure was lower when selumetinib was dosed before vs after dialysis, although individual exposure was variable. Overall, 32 subjects were included in the hepatic impairment study (mild, moderate, and severe impairment, N = 8 per group; healthy subjects, N = 8). Generally, dose-normalized total selumetinib exposure was increased by 25% to 59% in subjects with moderate and severe hepatic impairment compared with healthy subjects. Increasing Child-Pugh score, decreasing serum albumin, and increasing prothrombin time correlated with increasing unbound selumetinib exposure. In both studies, selumetinib was well tolerated with no new safety concerns. These studies will inform dose adjustment considerations in patients.

Evaluation of the Effect of Selumetinib on Cardiac Repolarization: A Randomized, Placebo- and Positive-controlled Crossover QT/QTc Study in Healthy Subjects.

PURPOSE: Selumetinib (AZD6244, ARRY-142886) is an oral, potent, and selective allosteric mitogen-activated protein kinase 1/2 inhibitor with a short t1/2. The purpose of this study was to characterize the effect of selumetinib on cardiac repolarization and a potential exposure-QT effect relationship. METHODS: A double-blind (selumetinib), randomized, 3-period crossover study was conducted to assess the effects of a single oral dose of selumetinib (75 mg) on the QTc interval compared with placebo, using moxifloxacin as an open-label positive control, in healthy male subjects aged 18 to 45 years. QT intervals were evaluated by using the Fridericia formula (QTcF) and the Bazett formula. Further analysis was conducted by using nonlinear mixed effects modeling to characterize any relationship between selumetinib exposure and QTc and was used to predict the effect if selumetinib 150 mg was administered. All adverse events were characterized and recorded. FINDINGS: A total of 54 healthy male subjects were enrolled, and 48 completed all treatments. Mean age was 27 years; four subjects were of Hispanic or Latino ethnicity, and 53.7% were White and 46.3% were Black. The BMI of subjects ranged from 19.4 to 29.6 kg/m2. After a single oral dose of selumetinib 75 mg, the highest upper bound of the 2-sided 90% CI for placebo-corrected, baseline-adjusted QTcF (ΔΔQTcF) over the 24-hour postdose measurement interval was 2.5 milliseconds, which was well below the 10-millisecond upper bound for concluding no effect. The relationship between ΔΔQTcF and selumetinib concentrations was adequately described by using a nonlinear mixed effect model. The mean estimated ∆∆QTcF interval prolongation based on the geometric mean Cmax of 75 mg selumetinib was 2.38 milliseconds (90% CI, 1.25 to 3.52), which was in good agreement with the statistical analysis results. The model also predicted mean ∆∆QTcF interval prolongations of 4.70 milliseconds (90% CI, 2.46 to 6.95) after a single supratherapeutic dose of selumetinib 150 mg, indicating the upper bound of 2-sided 90% CIs for ΔΔQTcF are predicted to be <10 milliseconds. Selumetinib, administered as a single 75 mg oral dose, was generally safe and well tolerated. IMPLICATIONS: Selumetinib 75 mg did not cause any QT/QTc interval prolongation in these healthy subjects, and selumetinib is not expected to have a clinically relevant effect on cardiac repolarization in patients at the anticipated therapeutic dose of 75 mg. The model also demonstrated the low potential for any QTc effects of selumetinib at doses higher than the standard therapeutic dose.

Metabolism, Excretion, and Pharmacokinetics of Selumetinib, an MEK1/2 inhibitor, in Healthy Adult Male Subjects.

PURPOSE: Selumetinib (AZD6244, ARRY-142886), an oral mitogen activated kinase 1/2 inhibitor, is in clinical development for the treatment of a variety of different tumor types. Herein, we report a study that determined the distribution, metabolism, and excretion of selumetinib in healthy male volunteers. METHODS: In this open-label, single-center, Phase I clinical trial, 6 subjects received a single 75-mg dose of [14C]-selumetinib. Blood and excreta samples were collected for pharmacokinetic and radiometric analyses. Tolerability monitoring was performed throughout the study. FINDINGS: The Cmax of plasma selumetinib was 1520 ng/mL at 1 hour postdose and declined with a t1/2 of 13.7 hours. Over a 216-hour postdose collection period, total dose recovery was 93% of the radioactive dose, with 59% recovered from feces and 33% from urine. Circulating drug-related material was primarily associated with plasma, with minimal distribution into red blood cells. Selumetinib was the major circulating drug-related component and accounted for 40% of the plasma radioactivity (mean of AUC0-72h pool). The major circulating metabolite (M2; accounting for 22% of the plasma radioactivity) resulted from multiple biotransformation pathways, including loss of the ethanediol moiety in combination with glucuronidation. A further 6 circulating metabolites were identified, each accounting for between 2% and 7% of plasma radioactivity. Selumetinib was a minor component in urine, accounting for ≤1% of the dose. M2 was the most abundant metabolite in urine, accounting for 10% of the dose, and there were 5 other metabolites accounting for between 1% and 10% of the dose. In feces, selumetinib accounted for a mean of 19% of the dose. Also present were 7 metabolites accounting for between 1% and 9% of the dose. The majority of the dose was recovered as metabolites, indicating that the liver is the major route of drug elimination. There were no tolerability concerns. IMPLICATIONS: The findings from this study will inform the label and will contribute to the understanding of the clinical pharmacology of selumetinib. ClinicalTrials.gov identifier: NCT01931761.